Ruby Brittle Star Ophioderma rubicundum Brittle stars, comprising over 2,000 species, are the most diverse class of echinoderms, but their nocturnal, cryptic habits make them seem rare. Most species shun light and favor dark crevices and shadows. Unlike the more familiar sea stars that walk ponderously with tube feet, most brittle stars move rapidly, using the fluid, swimming motions of their sinuous, slender arms.
